The present specification relates to a semiconductor switch device for switching an RF signal and to a method of making a semiconductor switch device for switching an RF signal.
Semiconductor devices such as power MOSFETs can be used as electric switches for high frequency pulse width modulation applications and as load switches in power applications. When used as load switches, where switching times are usually long, cost, size and on-resistance (Ron) of the switches are the prevailing design considerations. When used in high frequency pulse width modulation applications, the MOSFET may be required to exhibit small power losses during switching, which may impose an additional requirement for small internal capacitances. One of the most popular ways to evaluate the performance of a power MOSFET is to calculate the figure of merit (FOM), which may be defined as the product of the on-state resistance (Ron) and the off-state capacitance (Coff) of the device. Leakage currents within the device may also be important to the overall performance of the device.